The invention relates to phosphorosulfide containing compounds and to their use as lubricant additives. More particularly it relates to compounds made by reacting olefins with phosphorus pentasulfide and sulfur and/or a sulfur-containing compound.
The use of phosphorus compounds as load-carrying or antiwear agents and lubricant compositions is well known. The use of organic phosphorus compounds in combination with, for example, hindered phenols, is known from U.S. Pat. No. 3,115,465. It is also well known to use sulfurized olefins as lubricant additives as shown, for example, in U.S. Pat. Nos. 4,194,980 and 4,240,948.
U.S. Pat. No. 4,152,275 discloses olefin/sulfur/phosphorus lubricant additives formed by the reaction of sulfurized olefins and phosphorodithoic acids. U.S. Pat. No. 4,402,259 discloses metal salts for phosphorosulfurized hydrocarbons and lubricant compositions containing same. As far as applicant is aware, however, no art exists which suggests the herein-disclosed reaction product of olefins, phosphorus pentasulfide, sulfur and/or hydrogen sulfide.